"Cleveland knows they have time and are just accumulating picks," a personnel executive for an NFL team told USA TODAY Sports. "Sooner or later, (the) future will get here."

The executive spoke on condition of anonymity because NFL rules forbid clubs from publicly speaking about other teams' players.

A second NFL executive said he was shocked by the trade but understood why the Browns would do it now, with new coach Rob Chudzinski and general manager Michael Lombardi in their first season.

Richardson, the No.3 overall pick in the 2012 draft, and quarterback Brandon Weeden, the No.22 pick, were selected by former GM Tom Heckert for coach Pat Shurmur's offense. The Browns fired Heckert and Shurmur in December and dumped Richardson on Wednesday.

Weeden might be the next to go as the Browns continue to add draft selections to their current 2014 stock, which includes an extra third-rounder (from the Pittsburgh Steelers) and fourth (also from Indianapolis).

"From Cleveland's standpoint, they're 0-2 but in a honeymoon year with a new owner (Jimmy Haslam), team prez (Joe Banner), GM and head coach," the second executive said. "So, if you're gonna be bold, this is the time to do it."

Weeden is out this weekend due to a thumb injury. Fifth-year quarterback Brian Hoyer will make his second career start in place of Weeden at the Minnesota Vikings. And there's no guarantee Weeden will get his job back when healthy.

Scouts like what the Browns are building on both sides of the ball. But they lack a quarterback, and that could be the target with the higher of those first-round picks next year - probably a top-five pick with the way their season is headed.

The Browns also could package the two first-round picks if they need to move up for a targeted player. If they stand pat, another running back could be a possibility with the Colts' pick likely to be in the mid- to late-first round. Few runners are drafted as high as Richardson.

"Offensively, they've got an all-pro left tackle (Joe Thomas), all-pro center (Alex Mack). They do have a promising receiver in the (Josh) Gordon kid when they can keep him on the field. I think the (tight end Jordan) Cameron kid is on the way up. I just don't know about the quarterback yet."

And in a quarterback-driven league, that's what the Browns' decision boils down to: gathering all the ammunition to go get your guy and build around him, rather than building around a back who may have a limited shelf life.

The second executive speculated the Browns must have concerns about the long-term durability of Richardson, who ran for 950 yards and 11 touchdowns as a rookie but has gained 105 yards on his 31 carries so far this season.

Richardson had arthroscopic surgery to remove loose cartilage from his left knee during his first training camp in 2012. He played most of last season with two broken ribs and missed the finale after rolling an ankle. He hurt a shin in spring practices this year, then re-injured it in camp.

But the move could pay off immediately for the Colts, who are coming off a playoff season and want to put as much talent as possible around quarterback Andrew Luck, who was drafted two spots before Richardson at No.1 overall last year.

There's little question Richardson, 23, brings more physicality and overall talent to offensive coordinator Pep Hamilton's offense than Ahmad Bradshaw, who has averaged 4.1 yards in gaining 91 yards on 22 carries this season. The Colts also needed depth since No.2 rusher Vick Ballard (knee) is out for the season.

"If only the Colts had an (offensive line)," the first executive said.